A buddy of mine is looking at one for camping. Any advice I should give him about a water-cooled camper? Anything specific to that year to look out for?
Many of the technical articles are good reading as well. Just keep in mind that Lucas is trying to sell product - so some recommendations he gives help his bottom line.
Boy, I hesitate to weigh in, so much to say, so little time. The key is maintenance. Rebuild & replace everything if it hasn't already been done. My history with Vanagons (3 of them, 2 water-cooled 1.9L, one air-cooled 2.0) finds that, averaged over the years, one may expect to invest about $2000/year in maintenance, unless you do your own work. Known issues such as Vanagon syndrome (there is a fix) and blown head gaskets are familiar. Then there are the weird things, like a short on a wire causing the oil light to come on, floppy mirror syndrome, temp sensors failing, etc. It must become a love affair or the relationship will not survive.
I agree with what the others have said - except maybe I've been a bit more lucky. I have yet to have any major head gasket issues - but it is common. I've also never had a water pump issue.
The cooling system in general is a pain in the but. Also, Vanagon syndrome can be a bugger to trace down (because it can have multiple causes) - My advice would be to make sure that you a) Get a Bentley manual and b) sign up for the Vanagon e-mail list at vanagon.com
Now having said that I will say that similar to what I've been told about older buses - Vanagon's are remarkably easy to work on - I had zero mechanical experience before owning a Vanagon and have found I've been able to do most jobs myself - with help and advice from others. Right up to a whole engie removal and replacement.
They are great wonderful beasts - but can be frustrating at times. Keep up the maintenance, replace those fuel lines, and replace anything that might be suspect (within reason of course).